Preheat oven to 350°.
Grease an 8x12 or large oval glass baking dish.
In a large stock pot, boil the pasta according to package instructions.
Drain water in colander and return pasta to the stock pot.
Meanwhile in a medium-sized saucepan, melt 1/4 cup butter.
Whisk in flour and cook 1 minute whisking continuously, until mixture is bubbly.
Slowly stir in the cream adding about ¼ cup at a time.
Add salt, pepper and hot sauce and stir 1 more minute.
Turn heat to low and gradually stir in the mozzarella and shredded cheddar cheese.
Stir frequently until the cheese melts completely.
Sauce will be very thick.
Remove from heat.
Stir the drained, cooked macaroni into the cheese sauce.
Pour half of the mac and cheese mixture into the prepared baking dish.
Layer all of the cheese slices over top of the macaroni.
Top remaining half of the mac and cheese over cheese slices.
In a microwavable glass, melt remaining 1/4 cup butter in microwave.
Stir in the panko crumbs.
Sprinkle the bread crumb mixture over top of the mac and cheese.
(I used about half of the Panko bread crumb mixture).
Bake for 20-25 minutes at 350°, or until mixture is hot and bubbly.